Small boot cleanup (#1475)

src/boot/boot_main.c

@@ -1,5 +1,5 @@
 #include "prevent_bss_reordering.h"
-#include "global.h"
+#include "carthandle.h"
 #include "idle.h"
 #include "stack.h"
 #include "stackcheck.h"

src/boot/carthandle.c

@@ -0,0 +1,3 @@
+#include "carthandle.h"
+
+OSPiHandle* gCartHandle = NULL;

src/boot/viconfig.c

@@ -1,4 +1,4 @@
-#include "global.h"
+#include "libc/stdbool.h"
 #include "idle.h"
 
 void ViConfig_UpdateVi(u32 black) {

src/boot/z_std_dma.c

@@ -1,8 +1,10 @@
 #include "prevent_bss_reordering.h"
 #include "global.h"
+#include "carthandle.h"
 #include "fault.h"
 #include "stack.h"
 #include "stackcheck.h"
+#include "z64dma.h"
 #include "z64thread.h"
 
 size_t gDmaMgrDmaBuffSize = 0x2000;